The overall objective of the proposed resarch is to examine the possible regulation of glycolysis in brain by subcellular translocation by glycolytic enzymes. The partitioning of hexokinase, phosphoglucose isomerase, phosphofructokinase and lactic dehydrogenase as well as the non-glycolytic enzyme creatine kinase, between soluble and membrane-bound forms will be determined as a function of the energy status of synaptosomes and isolated neurons as a model of intact brain. The energy status of the isolated cells and synaptosomes will be varied in a controlled manner and the subcellular distribution of the five enzymes correlated with the energy status as determined by the concentrations of ATP, ADP and AMP.